Advancements in fields of science and technology lead to change in material technology. The choice between composites over traditional materials is a critical one.

A wide range of modern materials with efficient properties have evolved which includes composites along with traditional materials like wood or metals.

Traditional materials like wood, steel, and concrete show a wide range of applications from centuries. These are natural composites grown naturally in the environment or obtained by natural process.

Evolution of composites has changed material engineering. It has given an opportunity to designers to use new and better materials resulting in reduction in cost, increasing the efficiency and  utilizing the available resources.

Composites offer many such benefits in mechanical properties like toughness, corrosion resistance, durability, strength, low density.  

A composite, also known as fiber reinforced polymer(FRP)  with a polymer matrix reinforced in man-made natural fibers like carbon, glass, or aramid. 

Thermoplastic and Thermosetting are commonly used matrix forms in composites. Few include, unsaturated polyester, epoxy resins, vinyl ester resins, phenols.

These impressive properties have convinced engineers across North America to construct more than 500 bridges with composites.

Benefits of composites over traditional Materials 

Composites merge many of the best qualities that traditional materials offer. 

1. The two components of composites are reinforcement and matrix. The reinforcement is bounded by the matrix and provides the benefits of both the original components.
2. Example mud brick, in this mud brick and straw in a block are combined which results in a brick that is strong  against both squeezing and tearing or bending. Technically, it has both good tensile strength and good compressive strength.
3. Improvement in their  design process  made the end product applications in industries from aviation to renewable energy.
4. They have various applications in our daily lives as products we use in construction, transportation, aerospace, automobile sector, sports, manufacturing industries and many more.
5. Every year many of the traditional materials like steel and aluminum are being replaced by new composites. Their design flexibility had opened up new design opportunities for engineers.

One of the primary benefits of composites is their superior strength-to-weight ratio. Composite materials, such as fiber-reinforced polymers, offer exceptional durability and load-bearing capabilities while being significantly lighter than traditional materials like steel or concrete.

This makes them ideal for structures that require high strength without excessive weight, leading to significant advantages of composite materials in terms of improved efficiency and reduced construction costs.

Use Composites for benefits 

High strength to weight ratio –  carbon fibers weigh 20% as much as steel and 70% as aluminum with high stiffness compared to both the materials.

Durable – They never rust regardless of the environment. Their high dimensional stability allows them to maintain shape in both cold and hot conditions or irrespective of climate conditions.

This makes them popular in outdoor applications like wind turbines.  Engineers

Choose composites over traditional material to reduce maintenance cost and ensure long term stability. Major benefit for structures built to last decades.

Open up new design option

They offer many design opportunities compared to traditional metals. They can replace the assembly of metal parts with a single part. 

The surface texture can also be altered to fine degree of smoothness. Many of the recreational boat hulls are made of composites as they can be molded to a wide range of boat shapes. 

This reduces the maintenance cost by saving the production time.

Easier manufacturing techniques

With advancements in technology a new fabrication technique Digital composite manufacturing (DCM)  came into existence which simplified the manufacturing process without human assistance or man-power.

With this composites can be tailored in three dimensional both locally and globally by creating right strength-to-weight ratio, density, flexibility required for certain application.

Properties of Composites vs Traditional materials

Composites are gaining traction in a lot of industrial sectors. The advantages offered  made them ideal replacement for many of the traditional materials, they are fast gaining as the material of choice.

The major  traditional materials that are being replaced by composites include Steel, Aluminum, Wood , Concrete and Marble.

Let us have the comparison of these materials with composites-

Composites vs steel

Steel occupies a prominent place from construction of skyscrapers to bending of a steel beam. 

Steel making began thousands of years ago while the fabrication of composites from reinforced fibers debuted in the last decade.

But it is facing neck to neck competition from composites, which are replacing steel in various applications.

Composites offer many advantages over steels, which have intrinsic design limitations, susceptible to corrosion, density overall making its maintenance costly.

Considering the following attributes-

1. Lighter than steel – composites are 70% less in weight than steels.
2. Specularly  strong – with steel if greater strength is required then extra metal has to be added which increases the density.
3. Corrosion resistant– can withstand out-door applications regardless of the harshness of the environment which contradicts with steel.
4. Non- conductive in nature- steels are conductors of electricity whereas composites are superior insulators and do not respond to electricity.
5. Allow parts consolidation- A single part can replace many of the components in an assembly line, saving the process time and reducing the maintenance cost.

Composites vs Aluminum

Aluminum is one the most light weight, malleable material used in world wide manufacturing. 

Composites began to supersede aluminum as in designing Boeing 787 maximum of it is made of advanced composites which reduced its weight by 20% compared to conventional aluminum design.

Attributes include-

1. Extreme handling of tension – As aluminum is sensitive to tensile loads, composites offer the application the  required property as it can with-stand extreme tension conditions.
2. Precise distribution of weight- Aluminum alloys have less precise distribution of weight compared to composites.
3. Strong and flexible- Compared to standard aluminum alloys, composites offer high flexibility and good strength.
4. Vibration resistant- The non-elastic nature of composites dissipates the vibrational energy well suited for applications ranging from equipment mounts to athletic shoes which is absent in aluminum metals.

Composites vs Wood

Wood is a natural fiber made of cellulose and  lignin. They have a wide range of applications right from tools in stone age, carts in middle age and modern day furniture, home frame utilities etc.

Wood is a composite with its long cellulose continuous fibers held together by a lignin substance. 

 Wood has certain limitations as they are susceptible to pests, moisture and wraping.

The attributes include-

1. Increased life span- wood rots eventually while composites are durable. Consider the marine example in which the boats made of wood require continual maintenance. whereas composite boats have a life-span of about  50 plus years with routine maintanence.
2. Dimensionally stable- Retains their shape when exposed to harsh environments on the other hand wood shrinks, swells with humidity changes.
3. Easy for transportation – Because of the low density, composites can be transported easily.
4. Low maintenance- composite decks can be washed with soap and water while the decks made of wood have to be power washed.
5. Resistance to pests-  composites are pests free making them ideal for everything  from window frames to retaining walls.  

Composites vs Marble – Mechanical Properties

The most commonly used material in kitchen countertops is marble. They are heavy and easily stainable thus require significant manintanence. The complete composite classification gives the different categories.

Composites provide a host of benefits over marbles. 

Attributes include- 

1. Non-porous in nature – Unlike marbles, Composites can withstand disinfectant products without damaging the materials.
2. Easy maintenance –  As marbles are porous they require special materials for cleaning . they had to be maintained annually to prevent staining, which is not in the case of composites.
3. Esthetic appearance – composites can be easily made to any shape and can be customized to any color making best in designing different counters, showers, bathtubs etc. whereas granites must be carefully cut to required shape and are limited in number of colors.
4. Heat  resistant-  Granites absorb heat so they chip off when hot utensils are placed on them. Composites retain their integrity when exposed to high temperatures. 

Composites with all its attributes can be used in place of traditional materials to serve the purpose but cannot completely replace them.

When examining the pros and cons of composite materials, it is clear that the advantages of composites over traditional materials outweigh the drawbacks in many applications. Composite materials advantages and disadvantages must be carefully weighed, but the growing use of composites in everyday life is a testament to their increasing prominence in the field of civil engineering.

Further advancements will soon make the composites find their applications in every part of human lives.

Frequently Asked Questions (FAQ) – Composite Materials Used

Composites vs concrete

Concrete from decades  ago has been used as construction material. However the industries are showing interest in using composites instead of concrete, because of their impressive properties.

The attributes include-

1. Efficient installation- bridges made of composites are easier and fast to install than concrete. 

Concrete requires curing time and large equipment for installation which is not necessary in composite case.

2. Less maintenance- Maintenance of composite panels is easy as they have a long life -span whereas concrete panels undergo frequent repairs.

3. Increased life-span- Coastal and salt environment deteriorates the life of costly concrete products. Chemicals also shorten the life of concrete. Composites can with-stand any wear    and tear conditions thus extending the life of the product.